Problem in updating the JList

Hai,
i am doing a chat application in java applet. I used JList to display all the user present in the chat room, when a new user is loged in then using
user_list.setListData(user_list_vector);

i added the user and call this method
user_list.updateUI(); to update the list with new values.

But sometimes its get updated, in sometimes its not getting updated. To check whether the ListModel gets updated i used the following code System.out.println(user_list.getModel().getSize()); which shows new size of the user list, but its not getting updated. Tell me whats the problem

See how one of the leading financial services organizations uses Recorded Future as part of a holistic threat intelligence program to promote security awareness and proactively and efficiently identify threats.

Take a look at the Java API (http://java.sun.com/j2se/1.5.0/docs/api/). The bottom left pane is the list of classes, clicking up one will bring up a class description in the right pane, which gives you an overview of the class, descriptions for all of its methods and fields, and links back to methods and fields it's inherited. In this case, it's inherited the method validate, which takes no arguments, you call it like this: myList.validate(); According to the API:

"public void validate()

Validates this container and all of its subcomponents.

The validate method is used to cause a container to lay out its subcomponents again. It should be invoked when this container's subcomponents are modified (added to or removed from the container, or layout-related information changed) after the container has been displayed"

In other words, when you want to make sure that the component (in this case the JList) displays all the new information you just gave it, call validate(). Contrast that to updateUI:

"public void updateUI()

Resets the UI property with the value from the current look and feel."

That's not at all what you wanted. Just use validate instead, that's the method you thought you were calling.

This was posted to the Netbeans forum a Feb, 2010 and I also sent it to Verisign. Who didn't help much in my struggles to get my application signed.
------------------------- Start
The idea here is to target your cell phones with
the correct…

Basic understanding on "OO- Object Orientation" is needed for designing a logical solution to solve a problem. Basic OOAD is a prerequisite for a coder to ensure that they follow the basic design of OO. This would help developers to understand the b…